Gate effective-workfunction modification for CMOS

US7947549B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Dae-Gyu Park · Seojong-myeon, KR
• Michael P. Chudzik · Beacon, US
• Rashmi Jha · Wyoming, US
• Siddarth A. Krishnan · Newark, US
• Naim Moumen · Walden, US
• Vijay Narayanan · New York, US
• Vamsi K. Paruchuri · New York, US

Key dates

• Filing date: Feb 26, 2008
• Grant date: May 24, 2011
• Expiry date: Jan 10, 2029

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D30/62

Abstract

CMOS circuit structures are disclosed with the PFET and NFET devices having high-k dielectric layers consisting of the same gate insulator material, and metal gate layers consisting of the same gate metal material. The PFET device has a “p” interface control layer which is capable of shifting the effective-workfunction of the gate in the p-direction. In a representative embodiment of the invention the “p” interface control layer is aluminum oxide. The NFET device may have an “n” interface control layer. The materials of the “p” and “n” interface control layers are differing materials. The “p” and “n” interface control layers are positioned to the opposite sides of their corresponding high-k dielectric layers. Methods for fabricating the CMOS circuit structures with the oppositely positioned “p” and “n” interface control layers are also disclosed.